Diego Costa was involved in another training ground row, according to reports. (AFP/Getty Images)

Chelsea’s players were concerned with Diego Costa after the striker was involved in a bust-up with Nathaniel Chalobah earlier this season, according to reports.

The Daily Telegraph claims that the Spain striker ‘lost his temper’ with the 22-year-old midfielder during a training session before Chelsea’s 2-1 defeat to West Ham in the EFL Cup last October.

Even though the incident quickly blew over, the report claims that Costa’s team-mates were ‘concerned’ that Chalobah was going to suffer an injury.

Costa is set for new talks with Chelsea’s hierarchy this summer but the Premier League champions are reportedly willing to listen to large offers for the 28-year-old.

Nathaniel Chalobah and Diego Costa were involved in a bust-up earlier this season. (Getty Images)

Costa, who told Antonio Conte of his desire to return to Atletico Madrid on the Italian’s first day at the club, is understood to have not yet made up his mind about whether he wishes to leave Stamford Bridge this summer.

Tianjin Quanjian had a £76 million offer in the pipeline, but new Chinese Super League rules are now forcing clubs to curb their huge spend on transfers.

Atletico Madrid could still be an option for Costa due to the £86 million they will receive from Antoine Griezmann’s likely transfer to Manchester United.

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